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I'm sick of this car.

I've spent almost 2 years amassing parts and over 3 months assembling the engine. It has never run the way I want it to.

It's been to the tuner 4 times. Initial tune, twice for idling problems then adjusted for the GTR BOV that the majority of you say is so great. That GTR BOV has no dosing silliness but the boost hit is soft and it doesnt play well with the engine.

I've had 4 BOV's (SSQV, Synchronic, Greddy and now the GTR). The hated SSQV has the best overall normal street drivability and hardest hitting boost but the surging/dosing and associated drive line chatter at high boost is unacceptable.

So far, I replaced the coils with a new set of Splitfires, then a new igniter. Last week, when it went in for the GTR BOV adjustment, a Splitfire went bad so a new set of OEM Nissan coils and a new coil harness were installed. Also, my third set of sparkplugs in 8 months.

Got the car back this Saturday. Seemed to run fine until I boosted to the normal 18 PSI. Since then, at first start up, from sitting overnight, it runs normal until it warms to about 60 degrees C. It then will miss and the idle will be unpleasant until after 85 degrees C. Tuner says there is very little fuel or timing changes between 70 - 90 C. It rarely runs hotter than 84 C.

Of course, took him for a ride tonight and the car behaved relatively normal. My wife said a cloud of black smoke was emitted after I drove off in anger afterward, while boosting to 17 PSI. Perhaps my fuel pressure gauge is not correct and the PFC is doing its best to compensate. The softer boost hit and smoke could be attributed to over fueling but the A/F ratio and the sensor readings from the PFC are within normal operating parameters according my tuner. How can it be rich then?

The only thing left to do is verify the fuel pressure with a known good, calibrated gauge and send the PFC to Apexi for testing.

My tuner is Fujii from Fujii Dynamics. After living in Japan for a few years; I've learned that the locals cannot think outside of the box. I think that is the case here.

Any ideas?

1994 ECR33

Reconditioned head at NAPREC

Balanced crank, flywheel and pulley at NAPREC

PFC

HKS pod filter

Copy Super Suction

Q45 MAF

GT-R FMIC

HKS 2530Kai turbo kit

GTR BOV

HKS EVC V

HKS 1.6mm head gasket

JJR split/dump pipe

Cat back exhaust with resonator

Nismo Timing belt

HKS exhaust cam gear

Tomei Poncams

Nismo 555cc injectors and fuel regulator

GT-R fuel pump

As weather cools air is denser. You may find its pushing out past where it was tuned and in to an area of the map where the tuner has it running richer just in case you push up that boost or it dips in to that load point as a result of cold dense air.

As for the cloud of smoke/fuel when did it occur?

Start/middle/end of a gear or on the gear change? Have the better half give the car a flogging while you drive her car behind to get a better idea.

Last week, when it went in for the GTR BOV adjustment.

just on that part... what exactly did you adjust?

They are not adjustable.

Sounds like a vac leak perhaps, or a dirty AFM

Plugs in good condition?

Whats the FPR reading? Is it set right? (really a part that's not required part)

AFM is clean.

Plugs are less than a week old.

I know the GTR BOV requires no mechanical adjustment, it was the PFC tune for recirc. Yes, it needed it because it would not idle otherwise.

the fuel is about 40 PSI with the vacuum line off. Why is the adjustable FPR not required?

It ran fine (except for the dosing fun) with the SSQV, I doubt the vacuum issue.

It really doesn't matter, I have to return to the US in about a month, unexpectedly.

I'm going to get raped on the selling price regardless. I could part it out but I don't have the time. It would be nice to sell it for $7000 but that's not going to happen in its current condition.

In my frustration, I took off the GTR BOV to install the Greddy. I wanted to try the adjustable spring setting just for the hell of it.

A few weeks ago, I enlarged the cross pipe BOV port and the ECR33 adapter plate to match the Greddy valve and the OEM metal gasket was not going to work with the GTR BOV either. I used .8mm gasket material and it didn't look like it made full contact/seal.

It only had impressions from the BOV flange on the ends where the bolts are. I figure that the gasket wasn't soft enough or I didn't torque it correctly. So I sprayed a thick serving of silicone lube on both sides of the gasket and installed the Greddy.

Like magic, the car is fine.

I sincerely apologize for going off initially. My life are a little hectic right now. I'm going to be in Iraq in a few months and my wife is staying in Japan.

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